Apparatus for breaking the curl in traveling material webs formed of paper,cardboard or the like



Dec. 8, 1970 w, HEIDEPRIEM 3,546,067

APPARATUS FOR BREAKING THE CURL IN TRAVELING MATERIAL WEBS FORMED OF PAPER, CARDBOARD OR THE LIKE Flled March 10, 1967 Fig.1

2 Sheets-Sheet l 8, 1970 v w. HEIDEPRIEM 3,546,067

APPARATUS FOR BREAKING THE CURL IN TRAVELING MATERIAL WEBS FORMED OF PAPER, CARDBOARD OR THE LIKE Filed March 10, 1967 2 Sheets-Sheet 2 United States Patent Int. c1.1)21r 7/00 U.S. Cl. 162-271 3 Claims ABSTRACT OF THE DISCLOSURE Apparatus for breaking the curl or curvature in continuously moving material webs formed of paper, cardboard or the like and paid-off a supply roll. Such apparatus advantageously incorporates a freely rotatable round bar about which the web is partially wrapped, and such bar is supported to be freely rotatable at at least two backing rolls or groups of backing rolls bearing against the peripheral surface of the round bar. The invention further contemplates employing a control mechanism for continuously changing the breaking action automatically as a function of the changing diameter of the supply roll.

BACKGROUND OF THE INVENTION The present invention has reference to an improved apparatus for the so-called breaking or bending of traveling material webs formed of paper, cardboard or the like, wherein this breaking operation eliminates the roll curl or curvature of the paper and produces a flat condition of the web of material. Hench, the term breaking as employed herein refers to the bending of the material web in order to remove the curl appearing thereat due to such material having been wound upon a roll.

In paper handling machines, such as crosscutters, printing machines or other sheet-delivering machines working with a supply roll, the elimination of the roll curvature of the paper is of extreme importance for the troublefree further conveying and processing operations as well as for the trouble-free depositing of the individual sheets. Breaking devices have become known to the art which are formed by a stationary breaking ledge constructed to possess more or less sharp edges. The friction between the stationary breaking ledge and the paper web, particularly with high operating speeds, exerts a disadvantageous effect upon the surface of the paper web, and such disadvantageous effect increases with sensitive paper, especially with coated or supercalendered paper.

Now, in order to prevent this disadvantageous friction there have also already been employed revolving rollers or drums as a breaking device. These rollers must possess a relatively large diameter in order to prevent bending through or sagging, with the result that there is automatically brought about a reduced breaking action. Moreover, there have also been employed rollers possessing smaller diameters which, however, in order to prevent a bending through require a plurality of support bearings, the arrangement and construction of which unfavorably influence the effective looping angle or angle of wrap, and therefore, the breaking action. Furthermore, owing to the insufficient mounting and support of the roll considerable oscillations occur in the range of critical rotational speeds which lead to noisy operation of the breaking roll.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide an improved apparatus of the men- 3,546,067 Patented Dec. 8, 1970 tioned type which overcomes the above-mentioned drawbacks of the prior art structures.

Another, more specific object of this invention relates to the provision of a simple, highly effective breaking apparatus of the mentioned type which works without any appreciable friction, and further which manifests itself by its quiet operation free of oscillations also at high working speeds.

Now, in order to implement these and still further objects of the invention which will become more readily apparent as the description proceeds, the inventive apparatus is generally manifested by the features that a round bar which is partially wrapped by the paper web and functioning as a breaking device is mounted to be freely rotatable upon at least two support or backing rolls or backing roll groups which bear against the peripheral surface of the aforesaid round bar. A particularly advantageous and positive mounting of the round bar is achieved if three backing rolls are provided, two of which are arranged externally of the looping angle or angle of wrap of the round bar and the one remaining backing roll being located within such looping angle.

In order to alter the looping angle the backing rolls and thus the round bar are advantageously adjustably arranged between two guide rollers which guide the paper web. A particularly simple and effective construction results if the backing rolls and thus the round bar are displaceable in the direction of the bisector of the looping angle. However, the entire arrangement can also be undertaken in such a manner that the freely rotatble round or circular bar is mounted to be stationary, whereas the guide rollers which guide the paper web are constructed to be displaceable.

It is a known fact that the roll curl or curvature of a paper web which is pulled off of a supply roll increases as the diameter of the supply roll becomes smaller. As a result, in order to obtain an unchanged fiat condition of the broken paper web the requirement exists of changing the degree of the breaking action. In order to fulfill this requirement the invention further proposes displacing the backing rolls and therefore also the round bar as a function of the decreasing diameter of the supply roll.

According to a further aspect of the invention the bearing or contact pressure between the backing rolls and the round bar is adjustable. Owing to this measure it is possible to properly take into account the momentary working conditions and the properties of the paper web. Regulation or control of the contact or bearing pressure is undertaken in that, the backing roll which is arranged inside of the looping angle of the round bar is mounted, at pivotal lever means. Furthermore, it can be advantageous to mount the round bar so that it is exchangeable in order to be able, when necessary, to replace one round bar with another of a different diameter. A further possibility for changing the diameter of the round bar exists if this diameter is constructed to be changeable. Such possibility of varying the diameter of the round bar can be achieved if it is formed by an elastic hollow body which can be expanded or blown up by introducing a pressurized medium.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood, and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawing wherein:

FIG. 1 schematically illustrates a side view of a preferred embodiment of the inventive breaking apparatus;

.FIG. 2 is a cross-sectional view of the apparatus depicted in FIG. 1, taken along the line 22 thereof;

FIG. 3 schematically illustrates an embodiment of a control mechanism for the automatic regulation of the breaking operation; and

FIG. 4 depicts the control mechanism of FIG. 3 with the round bar in a position assumed towards the end of the delivery operation of the paper web from the supply roll.

DESCRIPTION OF THE PREFERRED EMBODIMENT The web 1 of paper, cardboard or the like material having a tendency to curl coming from a suitable supply roll which has not been depicted in FIG. 1, but could be similar to the supply roll 19 of FIG. 3, is delivered via the guide rollers 2 and 3 for further processing, for instance by a suitable crosscutter apparatus. The latter feeds into a deposit stack for receiving the sheets. Between the guide rollers 2 and 3 there is located a rotatable round or circular bar 4 constructed as a breaking device. As may be particularly clearly recognized enveloped by inspecting FIG. 1, the round bar 4 which is partially wrapped by the paper web 1 is freely rotatably mounted in a saddle formed by the support or backing rolls 5 and '6. These backing rolls 5 and 6, as best shown in FIG. 2, are likewise freely rotatably mounted in a bracket means 7 which is secured to a holder 8. Holder 8 is fixedly connected at each end with a respective plate member 9 which is displaceably guided in rail means 10.

Continuing, this round bar 4 braces itself at its end faces against ball-thrust bearings 11 which are secured to the plate members 9. In order to additionally secure the radial position of the round bar 4 there is provided a third support or backing roll 12 which bears against the peripheral surface of such round bar 4 at the region of wrap or looping of the paper web 1 about the aforesaid round bar. This backing roll 12 is mounted in pivotal lever means 13 having a respective pivot point or shaft 14 provided at the associated plate member 9. As also clearly recognized by referring to FIG. 1, at the therein depicted free end of the lever means 13 there engages through the agency of a pull rod 15 a hydraulic or pneumatic cylinder 16 which is likewise secured to the plate member 9. By appropriate actuation of the cylinder 16 it is possible to regulate the contact or hearing pressure between the round bar 4 and the backing rolls 5, 6 and 12. In this figure, reference numeral a also designates the previously considered looping angle or angle of wrap.

The up and down movement of the plate 9 and, therefore, the common displacement of the round bar 4 together with the backing rolls 5, 6 and 12 takes place through rotation of the threaded spindle 17 which engages in a threaded shoulder or portion 18 of the plate 9. By actuating the threaded spindle 17 it is possible to change the relative position of the round bar 4 and the guide rollers 2 and 3. Consequently, by taking into account the properties of the paper or cardboard web or by adjusting to the course of the unwinding operation it is possible to regulate the momentarily required breaking action.

Of particular importance is the changing of the breaking action by displacing the round bar 4 as a function of the diameter of the supply roll '19 since the roll curl or curvature of the paper or the cardboard continuously increases with decreasing roll diameter. Now in FIGS. 3 and '4 there is schematically illustrated an embodiment of an automatic regulation of the breaking operation, and specifically, FIG. 3 depicts the position of the round or circular bar 4 at the beginning of the paying-out operation, whereas FIG. 4 shows the position of the round bar 4 at the end of such paying-out or delivery operation.

In the case of the exemplary embodiment of control mechanism depicted in FIGS. 3 and 4 the braking force which continuously changes in =l n0Wn manner during the paying-out operation and acting upon the shaft of the supply roll 19 is utilized as an impulse transmitter for the adjustment of the round bar 4. The braking force regulator 20 is operably coupled with a suitable pressure measuring device 21 whose measurement value or result which is dependent upon the braking force produces an electrical impuse with the aid of the impulse transformer 22. This impulse transformer 22 acts upon a regulating or adjustment motor 24 through the agency of an amplifier 23. The regulating motor 24 operates the adjustment spindle 17 through the intermediary of the speed reduction drive 25, 'whereby the plate 9 and thereby the round bar 4 is moved during the course of the paying-out operation from the position shown in FIG. 3 into the position shown in FIG. 4.

In a similar manner the impulse for actuating the adjustment motor 24 can also be produced by a feeler which scans the diameter of the supply roll 19 or by a rotational speed monitor driven by the shaft of the supply roll. In each instance there is produced a continually changing breaking action which automatically increases with decreasing diameter of the supply roll.

I claim:

1. Apparatus for decurling continuously moving webs of material having a tendency to curl comprising a freely rotatable round bar partially enveloped by such web, so as to define a looping angle, at least two laterally spaced back-up roll means positioned adjacent said bar and engaging the circumference thereof on one side of such web, a third rolling contact support roll means positioned to engage such a web on the other side thereof and within said looping angle and press such bar into rolling contact with said at least two back-up roll means, means for regulating the contact pressure between all said roll means and said round bar comprising pivotal lever means for displaceably supporting said third rolling contact support roll means disposed within said looping angle.

2. Apparatus for decurling continuously moving webs of material having a tendency to curl comprising a freely rotatable round bar partially enveloped by such web, so as to define a looping angle, at least two laterally spaced back-up roll means positioned adjacent said bar and engaging the circumference thereof on one side of such web, a third rolling contact support roll means positioned to engage such a web on the other side thereof and within said looping angle and press such bar into rolling contact with said at least two back-up roll means, a pair of guide roll means for guiding such web, a vertically movable frame means mounted to be movable in a plane transverse to and between the vertical planes containing the axes of said guide roll means, said at least two laterally spaced back-up roll means being carried by said frame means, a pivot shaft means carried by said frame means in vertically spaced relation to said at least two back-up roll means, lever means extending from said pivot shaft means, said third roll means being carried by said lever means, and movable means operably connected between said frame means and said lever means for pivoting the same so as to regulate the contact pressure between said round bar and said third support roll means.

3. Apparatus as claimed in claim 2 and axial thrust applying ball means disposed between said frame means and said round bar.

References Cited UNITED STATES PATENTS 2,149,069 2/1939 Plympton et al 162271 2,918,897 12/1959' Zernov 162-197 3,185,616 5/1965 Zernov et a1. 162271 BENJAMIN A. BORCHELT, Primary Examiner C. T. JORDAN, Assistant Examiner 

